Shearhead for dryshowers

ABSTRACT

An elongated mounting body of a shearhead for dryshavers has opposite lateral side faces. A plurality of cutter blades are mounted on the mounting body straddling the same transversely of its elongation and having free edge portions which project laterally beyond the side faces thereof. Ribs are provided on and laterally project from the respective side faces and each surround and embed one of the edge portions of the respective cutter blades.

Unite tates [191 [111 3,724,72 Messinger [4 1 Apr. 3, 1973 [54].SHEARHEAD FOR DRYSHAVERS [56] References Cited [75] inventor: WerngrMessinger, Kronberg, Tau- UNITED STATES PATENTS nus, erman y 3,319,3335/1967 Futterer ..30/43.92 [73] Assignee: Braun Aktiengesellsehait,Frankfurt an Germany Primary Examiner-Robert C. Riordon [22] Filed: Apr.16, 1971 Assistant Examiner-Gary L. Smith [21] AppL No; 134,682AttorneyfMichael S. Striker 57 ABSTRACT [30] Foreign ApplicationPriority Data 1 An elongated mounting body of a shearhead for Apr. 23,1970 Germany ..P 20 19 744.8 dryshavers has pp lateral side faces. Aplurality Y of cutter blades are mounted on the mounting body (gillStraddling the Same transversely of its elongation and [581 I 346.51having free edge portions which project laterally beyond the side facesthereof. Ribs are provided on and laterally project from the respectiveside faces and each surround and einbed one of the edge portions of therespective cutter blades.

7 Claims; 2 Drawing Figures PATENTEDAFR3 ma 3. 724,072

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SHEARHEAD FOR DRYSHAVERS BACKGROUND OF THE INVENTION The presentinvention relates generally to an article of manufacture, and moreparticularly to an improved shearhead construction for use indryshavers.

It is known to provide dryshavers with shearheads in form of anelongated mounting body on which a plurality of cutter blades is mountedstraddling the mounting body. The mounting body is connected in suitablemanner with the drive of the dryshaver and is reciprocated or oscillatedin its longitudinal direction. The cutting edges of the cutter bladesare located closely adjacent the inside of a so-called shea'rfoil, thatis a very thin flexible piece of perforated-sheet material which ispressed into engagement with the skin of the user so that the beardstubble extends through the apertures and comes into contact with thecutter blades on the reciprocating cutter head or shearhead, therebybeing severed. (U.S. Pat. Nos. 3,527,093 and 3,379,333)

It is already known to make the cutter blade mounting member of theshearhead from synthetic plastic material, frequently from a glass fiberfilled or glass fiber reinforced synthetic plastic material. The purposeof utilizing such material, instead of metal which was originallyemployed, is to reduce the weight and therefore the oscillating mass ofthe shearhead and the resulting inertial forces as much as possible. Thecutter blades straddle the cutter blade mounting member as alreadypointed out, that is they surround the substantially hollow-cylindricalouter side of the cutter blade mounting member in direction transverselyof the elongation thereof and have free edges which can causedifficulties. It must be understood that the cutter blades themselvesare of substantially semi-circular configuration and that these freeedges are located at the opposite ends of the cutter blades. Because thecutter blades once mounted must subsequently be subjected to apost-treatment to re-sharpen them and eliminate any damage that may havebeen done to their cutting edges during installation on the cuttingblade mounting member, it is necessary that the free edge portions atthe opposite ends of each of the semi-circular cutter blades projectlaterally beyond the lateral side faces of the cutter blade mountingmember for sharpening purposes. If that were not the case then therelatively small grinding wheels utilized for this sharpening would veryquickly become clogged with particles of synthetic plastic materialwhich are abraided off the cutter blade mounting member, andparticularly in mass production such grinding wheels would very rapidlybecome unuseable.

While the prior art has solved this problem, that is as indicated aboveby having the lower edge portions of the semi-circular cutter bladesproject laterally beyond the lateral side faces of the cutter blademounting member, it has created a different problem in that theseprojecting edge portions are quite capable of damaging the very thin andvery flexible sheet-metal shearfoil whenever the latter is deflected byengagement with the skin of the user during operation of the dryshaver,inwardly in a sense which can bring it into engagement with theprojecting edge portions of the cutter blades which oscillate orreciprocate with the cutter blade mounting member. Also, there is thedanger that when from time to time the cutter blades must be cleaned,that is the shearfoil is removed and the shearhead is exposed forcleaning purposes, a user might hurt himself on these sharp portions.

SUNIMARY OF THE INVENTION It is, accordingly, an object of the presentinvention to overcome the aforementioned disadvantages.

More particularly, it is an object of the present invention to provideas a novel article of manufacture an improved construction which is notpossessed of these disadvantages outlined above.

A concomitant object is to provide such an improved construction whichis simple and inexpensive.

In pursuance of the above objects, and of others which will becomeapparent hereafter, one feature of the invention resides briefly statedin an elongated mounting body having opposite lateral side faces and aplurality of cutter blades mounted on the mounting body straddling thesame transversely of its elongation and having free edge portions whichproject laterally beyond the side faces. Ribs are provided on andlaterally project from the respective side faces and each surround andembed the respective edge portions.

The novel features which are considered as characteristic for theinvention are set forth in particular in the appended claims. Theinvention itself, however, both as to its construction and its method ofoperation, together with additional objects and advantages thereof, willbe best understood from the following description of specificembodiments when read in connection with the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWING FIG. 1 is a perspective viewillustrating a fragment of a shearhead embodying the present invention;and

FIG. 2 is a fragmentary detail view on an enlarged scale, illustrating afurther embodiment of the invention.

.1 0N F THE PREFERRED EWODIMENTS Discussing firstly FIG. 1, it will beseen that the cutter blade mounting member according to the presentinvention is of substantially semi-cylindrical hollow configuration. Ofcourse, only a portion of the elongation is shown in FIG. 1, and thetransversely extending end walls have been omitted for the sake ofclarity. It will be appreciated, however, that the mounting memberaccording to the present invention comprises two longitudinallyextending lateral portions 1 and 2 and a longitudinally extending upperor center portion 3, all of them being of synthetic plastic material,which may or may not contain glass fibers. At the opposite axial ends ofthis mounting member, the portions 1, 2, and 3 are all united bytransversely extending end walls which are unitary with the oppositeends of the portions 1, 2 and 3. As pointed out before, these end wallshave been omittedfor the sake of clarity and because they do not have abearing upon the present inventive concept..

In conventional manner a plurality of substantially semi-circular cutterblades 4 is provided which straddle the mounting member transversely ,tothe elongation thereof and which consist of a suitable blade of steel.In the constructions according to the present invention the lower edgeportions 9 and 10 of the blades 4 project laterally beyond the outerlateral sides 5 and 6 of the portions 1 and 2, respectively, with thedisadvantages which have been outlined in the introductory portion ofthe specification.

According to the present invention, however, I provide a pair of ribs ofwhich the rib 7 extends along the outer side 5 of the portion 1, whereasthe rib 8 extends along the outer side 6 of the portion 2. Each of theseribs embeds the lower free end portions 9 and 70,

. respectively of the cutter blades 4, so that they can no longerconstitute a danger to a person cleaning or otherwise working on theshearhead. When the cutter blades 4 are originally embedded in thematerial of the ribs 7 and 8 they project somewhat laterally beyond but,after the blades 4 have undergone the requisite grinding and sharpening,the edge portions 9 and 10 will be flush with the outer sides of theribs 7 and 8.

As shown in FIG. 1, the ribs 7 and 8 may be unitary (i.e., of one-piecewith) the respective portions 1 and 2. They can, however, also beseparate elements which are adhesively or otherwise secured to theportions 1 and 2. They may be each elongated and continuous, or, as FIG.2 shows, they may be each provided in form of a plurality of segments 77each of which may again be of one-piece with the respective lateralportion only 2 shown, or may be suitably secured thereto, but each ofwhich segment 11 only embeds one edge portion 9 or 10, respectively. Inother words, the ribs 7 and 8 may be discontinuous in longitudinaldirection according to the embodiment of FIG. 2.

The ribs may be secured to the lateral portions if they are not ofone-piece with them in various ways, by adhesive means, as pointed outbefore, but also by clamping, by pressing or the like. By resorting tothe present invention, I have disclosed a simple way of preventing thepossibility of damage to the shearfoil by the edges of the bladeportions 9 and 10, be it damage by engagement with the shearfoil due topressure, a blow or a fall, or be it as a result of tearing open of theshearfoil during operation of the shaver under the influence of pressureexerted on the shearfoil when the latter is guided over the skin of theuser. At the same time, the possibility of clogging of the grindingwheels utilized for grinding the cutting edges of the blades 4 isreduced to a minimum and damage or injuries as ai 8 is to dampen anytendency of the shearhead to dip or tilt during its reciprocatorymovement, whereby such movement is stabilized.

It will be understood that each of the elements described above, or twoor more together, may also find a useful application in other types ofconstructions differing from the types described above.

While the invention has been illustrated and described as embodied in anovel article of manufacture, it is not intended to be limited to thedetails shown, since various modifications and structural changes may bemade without departing in any way from the irit of the presentinvention.

W1thou further analysis, the foregoing Wlll so fully reveal the gist ofthe present invention that others can, by applying current knowledgereadily adapt it for various applications without omitting featuresthat, from the standpoint of prior art, fairly constitute essentialcharacteristics of the generic or specific aspects of this inventionand, therefore such adaptations should and are intended to becomprehended within the meaning and range of equivalence of thefollowing claims.

What is claimed as new and desired to be protected by Letters Patent isset forth in the appended claims.

I claim:

1. As a novel article of manufacture, a shearhead for dryshavers,comprising an elongated mounting member having opposite lateral sidefaces; a plurality of cutter blades mounted on said mounting bodystraddling the same transversely of the elongation thereof and havingfree edge portions which project laterally beyond said side faces; andribs provided on and laterally projecting from the respective sidefaces, each of said ribs surrounding and embedding respective ones ofsaid edge portions.

2. A novel article of manufacture as defined in claim 1 wherein saidmounting member is of synthetic plastic material.

3. A novel article of manufacture as defined in claim 2, wherein saidsynthetic plastic material comprises glass fibers embedded therein.

4. A novel article of manufacture as defined in claim 1 wherein saidribs are of one piece with said mounting member.

5. A novel article of manufacture as defined in claim 1, wherein saidribs are separate elements and secured to said mounting member.

6. A novel article of manufacture as defined in claim 1, wherein saidribs each extend longitudinally of said mounting member.

7. A novel article of manufacture as defined in claim 6, wherein saidribs are each subdivided into a plurality of sections.

1. As a novel article of manufacture, a shearhead for dryshavers,comprising an elongated mounting member having opposite lateral sidefaces; a plurality of cutter blades mounted on said mounting bodystraddling the same transversely of the elongation thereof and havingfree edge portions which project laterally beyond said side faces; andribs provided on and laterally projecting from the respective sidefaces, each of said ribs surrounding and embedding respective ones ofsaid edge portions.
 2. A novel article of manufacture as defined inclaim 1, wherein said mounting member is of synthetic plastic material.3. A novel article of manufacture as defined in claim 2, wherein saIdsynthetic plastic material comprises glass fibers embedded therein.
 4. Anovel article of manufacture as defined in claim 1, wherein said ribsare of one piece with said mounting member.
 5. A novel article ofmanufacture as defined in claim 1, wherein said ribs are separateelements and secured to said mounting member.
 6. A novel article ofmanufacture as defined in claim 1, wherein said ribs each extendlongitudinally of said mounting member.
 7. A novel article ofmanufacture as defined in claim 6, wherein said ribs are each subdividedinto a plurality of sections.